Petroleum lubricant stabilized against hydrocarbon-metabolizing micro-organisms



United States Patent PETROLEUM LUBRICANT STABILIZED AGAINST HYDROCARBON-METABOLIZING MICRO OR- GANISMS Edward B. Hodge, Terre Haute, Ind., assignor to Commercial Solvents Corporation, Terre Haute, Ind., a corporation of Maryland No Drawing. Application August 1, 1957 Serial No. 675,528

3 Claims. (Cl. 252-515) My invention relates to a stabilized petroleum lubricant and more particularly to a process for the production of stabilized petroleum lubricants containing 5-amino-2,2,5- trimethyl-3-aza-1-hexanol as the active stabilizing agent.

It is Well known that organisms from the group consisting of Corynebacterium, Achromobacter, Nocardia, Pseudomona, Mycobacterium, etc., metabolize petroleum hydrocarbons and fatty acids and thereby produce undesirable oxidation products.

The petroleum industry has long been interested in the stabilization of various petroleum products such as cutting oils, hydraulic oils, hydraulic fluids, etc., against break-down by bacteria which metabolize the hydrocarbons with the concurrent formation of deleterious metabolites.

Many compounds have been used as stabilization agents in lubricants, but very few have been found to be commercially successful due to the fact that the compounds are unstable, or are not active against a wide variety of microorganisms.

I have now discovered that 5-amino-2,2,5-trimethyl-3- aza-l-hexanol is very active against petroleum metabolizing microorganisms. This compound can be easily prepared in good yields by the method set out in US. Patent 2,393,825. I have found that in some instances I can obtain total inhibition of bacterial growth in petroleum lubricants at concentrations as low as 0.005%. I prefer to include at least 0.0075 in most petroleum formulations. However, I can employ amounts up to 10.0% of the active agent when the latter is soluble to this extent in the particular petroleum hydrocarbon compositions.

I have found that 2-amino-2,2,5-trimethyl-3-aza-1- hexanol is an effective bacteriostatic agent in petroleum containing lubricants such as cutting oils, penetrating oils, grinding lubricants, iron tinning lubricants, core oils, hydraulic fluids, etc.

The following examples set out lubricating compositions in which 5amino-2,2,5-trimethyl-3-aza-1-hexanol acts as an effective bacteriostatic agent. It is not intended that my invention be limited to the compositions, portions, or lubricants set out below, but rather I intend for all the equivalents and variations obvious to those skilled in the art to be included within the scope of this specification and the attached claims.

Example I Percent by weight Light mineral oil 85 Oleic acid 2-amino-2-methyl-1-propanol ....--,-..--a--.--.-- 5

ICC

Example II A steam cylinder oil composition having the following formula:

S.A.E. lubricating oil Oleic acid 10% 5-amino-2,2,5-trimethyl-3-aza-l-hexanol 750'y/ml.

was diluted and tested by the method of Example I. The stabilized composition was found to exhibit no growth while the control composition exhibited a bacterial growth of 4+.

Example III A core oil having the following composition:

Crude tall oil 25% Fuel oil 35% Tall oil ester (glycol or glycerol) 40% 5-amino-2,2,5-trimethyl'3-aza-hexanol 7507/1111.

was diluted and tested by the method of Example I. The stabilized portion was found to exhibit no bacterial growth while the control composition exhibited a growth of 4+.

Example IV A cutting oil and grinding lubricant having the following composition:

Tallow 65% Paraflin wax 29% Beeswax 1% Citric acid 1.3% Oxalic acid 1.3% Potassium citrate 1.3% Urea 0.4% 5-amino-2,2,5-trimethyl-3-aza-1-hexanol 7507/1131.

was diluted and tested by the method of Example I. No bacterial growth was found on the stabilized composition while the control composition exhibited a bacterial growth of 4+.

Now having described my invention, what I claim is:

1. A petroleum lubricant stabilized against hydrocarbon-metabolizing micro-organisms containing a small but suflicient amount to inhibit said petroleum metabolizing micro organisms of 5 amino 2,2,5 trimethyl-3-aza-lhexanol.

2. An aliphatic petroleum hydrocarbon lubricant stabilized against hydrocarbon-metabolizing micro-organisms containing from 0.005% to 10.0% by weight of 5- amino-2,2,5-trimethyl-3-azal-hexanol.

3. An alphatic petroleum hydrocarbon lubricant stabilized against hydrocarbon-metabolizing micro-organisms containing from 0.0075 to 10.0% by weight of 5- amino-2,2,5-trimethyl-3-aza-1-hexanol.

References Cited in the file of this patent UNITED STATES PATENTS 2,393,825 Senkus Jan. 29, 1946 

1. A PETROLEUM LUBRICANT STABILIZED AGAINST HYDROCARBON-METABOLIZING MICRO-ORGANISMS CONTAINING A SMALL BUT SUFFICIENT AMOUNT TO INHIBIT SAID PERTOLEUM METABOLIZING MICRO-ORGANISMS OF 5-AMINO -2,2,5-TRIMETHYL-3-AZA-IHEXANOL. 